Clinical perspective, offered as context rather than as advice.
My HPLC chromatogram analysis for certificates of analysis — I sent my batch to Janoshik and here's what the results showed:
Main peak retention time: 16.6 minutes (consistent with semaglutide reference standard)
Peak purity: 98.5%
Related substances: 0.7% (single impurity at 10.4 minutes — likely a synthesis intermediate)
Mass spec: m/z 4113.5 (matches expected molecular weight)
This is a clean result. The mass spec confirmation is particularly important — it proves the molecule is actually semaglutide and not a substitution.
Clinical perspective, offered as context rather than as advice.
I tested my certificates of analysis batch through Janoshik — 99.5% purity. That's within acceptable range for compounded peptides. Turnaround was 12 business days.
The test costs ~$137 but gives you actual HPLC chromatography data plus mass spec confirmation. For the peace of mind alone, it's worth every penny. I test every new batch from a new vendor.
TrialNerd_Beth said:I tested my certificates of analysis batch through Janoshik — 99.5% purity.
Second this. Posting only so the count is not one.
Sigma-Aldrich — Research-Grade Standards
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Shop Reference StandardsTrialNerd_Beth said:I tested my certificates of analysis batch through Janoshik — 99.5% purity.
My vendor review relevant to certificates of analysis: ordered 6 times from my current compounder. Consistency has been excellent.
Shipping: 3-day with temperature monitor
Packaging: Professional, discreet, proper labeling with lot/batch numbers
Purity: 99.3% average across orders (Janoshik verified)
Customer service: Responsive within 1 hours
Price: $147/month for semaglutide 1.7mg equivalent